You know, I most certainly do not live in a museum. The OP asked for appropriate punishment - the only appropriate punishment for a dog eating something is to discipline the adult humans for not preventing it - especially something like a wallet with money & credit cards.
With a current 4 dog (with a 4 month old puppy) household, my dogs are all trained to leave what is not theirs alone - but they are trained; not merely punished. I will actually sit on the floor with food and eat and wait for them to try to take it; and they are told NO when they do. They are trained for what is theirs to take versus what is mine and off limits.
If they do take something that is not put away - it is the humans fault. Either for leaving something the dog has not been trained to resist, or for not training their dog. You know
dogs like white stuff, paper, socks, undies, shoes, food etc so why would you leave them somewhere to be destroyed - or if they are left about - why leave a pup free to get at them?
Good for you for bragging on punishing your dog in the name of training - you TUG on the skin under your dog's chin????????????? Just so we are clear - you are speaking of the skin under the chin and not the scruff of the neck?
I have a bit of a different outlook on this issue then the first poster. I do not want live in a museum. My home is not messy but I do have things around especially around this time of year. Usually, when my dogs grab something they shouldn't I let out a very loud "NO, LEAVE IT". I return the item back to where it should be and wait t see if they try again. I grab the loose part under the chin and give it tug and repeat "LEAVE IT". LOL through the dogs I have had in my life I have been known to give a tap on the bum and I am not afraid to admit it. "Trainers" have got a little out of control with this "all positive reinforcement" stuff. Most of all be on your toes waiting to give the correction and be consistent. Also, more chewies and toys of his own. Dog need to be taught manners.